Fire-alarm.



No. 756,686. PATENTED APR. 5, 1904. F. MOFADDEN.

7 FIRE ALARM. APPLIUA'IION FILED APR. 16, 1903. N0 MODEL. 2 SHEETS-SHEET 1.

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No. 756,686. PATENTED APR. 5, 1904. F. MoFADDEN.

FIRE ALARM.

APPLIOATION IILBD APR. 1c, 1903. NO MODEL. 2 sums-41mm 2.

U: 7 6 Mn; X

Patented April 5, 1904.

UNITED STATES PATENT EEicE.

FRANK MGFADDEN, OF VANATTA, OHIO.

FIRE-ALARM.

SPECIFICATION forming part of Letters Patent No. 756,686, dated April 5, 1904. Application filed April 16,1903. Serial No. 152,266- (No model.)

To all whom. it puny concern.-

Be it known that I, FRANK MGFADDEN, a citizen of the United States, residing at Vanatta, in the county of Licking and State of Ohio, have invented certain new and useful Improvements in Gas-Alarms, of which the following is a specification.

The purpose of this invention is to devisea novel mechanism for sounding an alarm in the event of the flame of a gas light or stove becoming extinguished from any cause, thereby giving warning and preventing casualties resulting from escaping gas, such as explosion and asphyxiation.

The alarm comprises a thermal device, a gong or like audible signal, and a train of gearing for escaping and sounding of the alarm when released by contraction of the thermal device incident to cooling of same after the flame or light has been extinguished.

For a full description of the invention and the merits thereof and also to acquire a knowledge of the details of construction of the means for effecting the result reference is to be had to the following description and drawings hereto attached.

WVhile the essential and characteristic fea, tures of the invention are susceptible of modification, still the preferred embodiment of the invention is illustrated in the accompanying drawings, in which Figure 1 is a perspective View showing the alarm used in connection with a gas-light. Fig. 2 is a front view, the thermal device being in section and a part of the frame of the alarm mechanism being broken away. Fig. 3 is a seetionalview at the line XX of Fig. 2. Fig. 4 is a top plan view. Fig. 5 is a detail perspective view of the detent.

Corresponding and like parts are referred to in the following description and indicated in all the views of the drawings by the same reference characters.

The alarm comprises a thermal device 1, gong 2, alarm mechanism 3, and detent a, the latter having positive connection with the thermal device and automatically actuated thereby for releasing the alarm mechanism when the flame becomes extinguished. The thermal device within the purview of the invention may be of any construction readily affected by changes in temperature so as to effect automatic release of the alarm mechanism whereby a warning is sounded. In the preferable construction the thermal device comprises pan or cup 5 and a diaphragm 6, the latter closing the open side of the pan or cup and secured at its edges to the rim of said pan or cup and forming a tight joint therewith, so as to confine the air, this being essential in order to secure the effective and successful operation of the device. The diaphragm 6 may be of any construction so as to readily move according to the pressure of the confined air.

The detent l consists of a rod or bar having adjustable connection at its lower end with a socket 7, applied centrally of the diaphragm and adapted to make scrcw-thread connection with said detent to admit of adjusting same to release the alarm mechanism Within aslight variation of a given temperature.

' The alarm mechanism comprises frame 8 and a train of gearing of any approved construction and comprising escape-wl1eel9,with which detent 4 cooperates to hold the alarm mechanism out of action when the lamp or stove is burning. The alarm mechanism is operated by a spring in the usual Way, said spring being adapted to be wound by means of key 10 in the well-known manner. The hammer 11 is adapted to strike against gong 2, and its stem is connected at its upper end to pallet-lever 12, which cooperates with escape-wheel 9 when the alarm mechanism is released.

The working parts are secured to a suitable base 13 and may be housed in any desired way for protection. WVhen using the alarm. it is placed so that the thermal device comes within the heating Zpne of the light or flame,

whereby the air confined in the chamber of the the alarm. In the event of the heat regaining the given degree before the alarm mechanism is run down the detent Will again be projected so as to engage With a tooth of the escape-Wheel and restrain the alarm mechanism until the heat again falls below the predetermined degree. In the event of the light or flame becoming extinguished the thermal device cooling quickly Wlll' effect a sounding of the alarm, thereby apprising anyone Within hearing of the alarm that the light or flame has gone out, so that the gas may be turned off, thereby preventing the fatalities frequently attributable to escaping gas.

Having thus described the invention, What is claimed as new is' In combination, a pan or cup, a diaphragm closing the open side thereof and provided at a central point With a threaded extension, an alarm mechanism comprising an escape-Wheel, a gong, a hammer for sounding an alarm upon said gong and connected With the pallet-lever of the alarm mechanism, and a detent having screw-thread connection With the extension of said diaphragm and adapted to extend across the path of the teeth of said escape- Wheel to hold the alarm mechanism in restraint under normal conditions, substantially as set forth.

In testimony whereof I afiix my signature in presence of tWo Witnesses.

FRANK MOFADDEN. [L. s]

N itnesses:

CLARA CAIN, LIZZIE BARRICK. 

